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diff --git a/doc/src/sgml/html/tutorial-table.html b/doc/src/sgml/html/tutorial-table.html new file mode 100644 index 0000000..6c80b6f --- /dev/null +++ b/doc/src/sgml/html/tutorial-table.html @@ -0,0 +1,69 @@ +<?xml version="1.0" encoding="UTF-8" standalone="no"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>2.3. Creating a New Table</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="tutorial-concepts.html" title="2.2. Concepts" /><link rel="next" href="tutorial-populate.html" title="2.4. Populating a Table With Rows" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">2.3. Creating a New Table</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="tutorial-concepts.html" title="2.2. Concepts">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="tutorial-sql.html" title="Chapter 2. The SQL Language">Up</a></td><th width="60%" align="center">Chapter 2. The <acronym class="acronym">SQL</acronym> Language</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 15.5 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="tutorial-populate.html" title="2.4. Populating a Table With Rows">Next</a></td></tr></table><hr /></div><div class="sect1" id="TUTORIAL-TABLE"><div class="titlepage"><div><div><h2 class="title" style="clear: both">2.3. Creating a New Table</h2></div></div></div><a id="id-1.4.4.4.2" class="indexterm"></a><p> + You can create a new table by specifying the table + name, along with all column names and their types: + +</p><pre class="programlisting"> +CREATE TABLE weather ( + city varchar(80), + temp_lo int, -- low temperature + temp_hi int, -- high temperature + prcp real, -- precipitation + date date +); +</pre><p> + + You can enter this into <code class="command">psql</code> with the line + breaks. <code class="command">psql</code> will recognize that the command + is not terminated until the semicolon. + </p><p> + White space (i.e., spaces, tabs, and newlines) can be used freely + in SQL commands. That means you can type the command aligned + differently than above, or even all on one line. Two dashes + (<span class="quote">“<span class="quote"><code class="literal">--</code></span>”</span>) introduce comments. + Whatever follows them is ignored up to the end of the line. SQL + is case insensitive about key words and identifiers, except + when identifiers are double-quoted to preserve the case (not done + above). + </p><p> + <code class="type">varchar(80)</code> specifies a data type that can store + arbitrary character strings up to 80 characters in length. + <code class="type">int</code> is the normal integer type. <code class="type">real</code> is + a type for storing single precision floating-point numbers. + <code class="type">date</code> should be self-explanatory. (Yes, the column of + type <code class="type">date</code> is also named <code class="structfield">date</code>. + This might be convenient or confusing — you choose.) + </p><p> + <span class="productname">PostgreSQL</span> supports the standard + <acronym class="acronym">SQL</acronym> types <code class="type">int</code>, + <code class="type">smallint</code>, <code class="type">real</code>, <code class="type">double + precision</code>, <code class="type">char(<em class="replaceable"><code>N</code></em>)</code>, + <code class="type">varchar(<em class="replaceable"><code>N</code></em>)</code>, <code class="type">date</code>, + <code class="type">time</code>, <code class="type">timestamp</code>, and + <code class="type">interval</code>, as well as other types of general utility + and a rich set of geometric types. + <span class="productname">PostgreSQL</span> can be customized with an + arbitrary number of user-defined data types. Consequently, type + names are not key words in the syntax, except where required to + support special cases in the <acronym class="acronym">SQL</acronym> standard. + </p><p> + The second example will store cities and their associated + geographical location: +</p><pre class="programlisting"> +CREATE TABLE cities ( + name varchar(80), + location point +); +</pre><p> + The <code class="type">point</code> type is an example of a + <span class="productname">PostgreSQL</span>-specific data type. + </p><p> + <a id="id-1.4.4.4.8.1" class="indexterm"></a> + + Finally, it should be mentioned that if you don't need a table any + longer or want to recreate it differently you can remove it using + the following command: +</p><pre class="synopsis"> +DROP TABLE <em class="replaceable"><code>tablename</code></em>; +</pre><p> + </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="tutorial-concepts.html" title="2.2. Concepts">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="tutorial-sql.html" title="Chapter 2. The SQL Language">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="tutorial-populate.html" title="2.4. Populating a Table With Rows">Next</a></td></tr><tr><td width="40%" align="left" valign="top">2.2. Concepts </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 15.5 Documentation">Home</a></td><td width="40%" align="right" valign="top"> 2.4. Populating a Table With Rows</td></tr></table></div></body></html>
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